Elster A1140 Hash calculation

Hello,
I am getting a data over RS485 interface in IEC-62056-21 protocol on elster A1140 smart meter. But i get this random generated key from the meter and it hashed with the remote password i put in which is 00000000 and then it sends the hashed password to the meter. I followed bunch of examples in the internet but no success unfortunately. Please help me on this issue. I have put the received frame and the received key and generated password.
example 1:
B0A692CB07930FD1 > this is the received key
61F79994CB6EAD8E > this is the generated password
example 2:
EA864EBC197ED3D3 > this is the received key
BD73F17DA6F4D7BA > this is the generated password

this is the overall frame i am receiving.
Logon
COM3-> /?094!<CR><LF>
<-COM3 /GEC5120510070213@000<CR><LF>
COM3-> <ACK>056<CR>
COM3-> <LF>
<-COM3 <SOH>P0<STX>(FD04BE65D6157FA9)<ETX><GS>
COM3-> <SOH>P2<STX>(0000000000000000)<ETX>b
<-COM3 <ACK>
COM3-> <SOH>R1<STX>798001(10)<ETX>e
<-COM3 <STX>(30303030303030303035303734343934)<ETX><CR>
COM3-> <SOH>R1<STX>795001(08)<ETX>a
<-COM3 <STX>(505F323238303532)<ETX>{
COM3-> <SOH>P2<STX>(669A287D6388D770)<ETX><DC2>
<-COM3 <ACK>
COM3-> <SOH>W1<STX>576001(456C73746572202020202020)<ETX><SYN>
<-COM3 <ACK>